X-ray images can be stored in so-called storage phosphors, whereby X-ray radiation passing through an object, for example a patient, is stored as a latent image in a phosphor layer. In order to read out the latent image, the phosphor layer is irradiated with stimulation light, and so stimulated into emitting emission light. The emission light, the intensity of which corresponds to the image stored in the phosphor layer, is collected by an optical detector and converted into electric signals. The electric signals are further processed, as required, and finally made available for examination, in particular for medical/diagnostic purposes, whereby they are displayed in corresponding display equipment, such as eg. a monitor or a printer.
In several areas of application of this technology, also known as computer radiography, due to medical stipulations care should be taken to ensure that the X-ray information stored in the phosphor layer is collected as completely as possible at least in the area around the edge of the phosphor layer so that the greatest amount possible of diagnostic information is made available. This is especially applicable, for example, for mammographic applications.
With established processes in accordance with the prior art, phosphor layers are therefore scanned, ie. read out, as accurately as possible up to the edge of the layers. For this, relatively complex steering of the scanner is generally required. At the same time, with the established processes greater position tolerances for the phosphor layer relative to the scanner are mostly not taken sufficiently precisely into consideration, so that in some cases an undesirably or unpermissibly high level of loss of diagnostic information can occur.
It is the aim of the invention to provide a process for the collection and presentation of an X-ray image stored in a phosphor layer, whereby to the greatest extent possible, all of the X-ray information stored in the phosphor layer can be collected and presented, with increased reliability.